Senate Democrats failed to break a filibuster of a campaign finance reform bill Thursday, marking the second time their DISCLOSE Act has fallen short of the votes necessary to be debated on the floor.

The chief Senate sponsor of the bill, Democrat Chuck Schumer of New York, had tried to make a last-ditch appeal to his Republican colleagues Wednesday by saying Democrats would be open to amendments — including a push back of the legislation's effective date to the next campaign cycle. But GOP senators were unconvinced by the appeal on a bill they believe should have been more openly negotiated and merited a committee debate.

The legislation required 60 votes to move forward and failed, 59-39, without a single Republican breaking ranks.

Members from both sides of the aisle tried to score Thursday's failed vote as a messaging victory, with Democrats charging that Republicans were siding with corporate special interests and Republicans charging that Democrats had crafted a bill that favored their campaign status. Minority Leader Mitch McConnell (R-KY) dismissed the vote Wednesday on the floor as "pure politics" and the legislation overall as a "on bill that amounts to little more than an incumbency protection act for Democrats in Congress.”

But Schumer — the one-time head of the Democrat's Senate campaign arm who had a substantial role in shaping the bill — insists that the legislation was aimed at increasing transparency of campaign contributors, not to create new restrictions on who can give. The DISCLOSE Act was crafted as a response to the January 2010 Citizens United decision rendered by the Supreme Court that overturned parts of the McCain-Feingold campaign law and deemed corporate giving protected free speech.

By failing to even open debate on DISCLOSE, the Senate has added another item on its list of bills that cleared the House only to be stuck in legislative limbo.

The Senate version of the bill had included what Democrats believed were strengthening provisions, including requiring campaigns to electronically file versions of their disclosure reports to the Federal Election Commission. House candidates and incumbents are currently required to do so, but Senate campaigns file paper reports, which are then posted online after being scanned into electronic format.

The bill also would have require corporations, unions and advocacy groups to disclose their involvement in political ads or mailings in the closing months of campaigns.

It is unclear whether Senate Democrats will try again on the bill during a lame-duck session post-elections, but even then approval would be an uphill battle.